Low mpg
#21
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There are three O2 sensors. One for each side ahead of the single catalytic converter, and one after the single catalytic converter.
If your fuel trims are normal, and your front O2 sensor voltages are cycling across 0.45 volt - then your front O2 sensors are reading fine. Rear O2 sensor just checks catalytic converter function for the PCM.
These vehicles can really have some poor mileage in the Wintertime. I have seen the 11 mpg on mine around town before in the Winter with warming up and stuff and 4WD. Agree with the 14 mpg city during the Summer. Max of 18 mpg on the highway on a level road.
Sticking brake calipers are one thing to check though and they can really kill gas mileage. Another thing is how you drive - a lot of people don't realize that slow easy starts use much less gas than does fast acceleration. Keeping steady speed (not riding someone's butt) is another thing that helps mileage. Another thing is wind resistance - slow down - pushing a brick through the air at 60 mph is a lot easier than at 75.
My advice ...... be happy it runs good. Don't buy a Blazer if mpg is your expectation. They are not known for it.
If your fuel trims are normal, and your front O2 sensor voltages are cycling across 0.45 volt - then your front O2 sensors are reading fine. Rear O2 sensor just checks catalytic converter function for the PCM.
These vehicles can really have some poor mileage in the Wintertime. I have seen the 11 mpg on mine around town before in the Winter with warming up and stuff and 4WD. Agree with the 14 mpg city during the Summer. Max of 18 mpg on the highway on a level road.
Sticking brake calipers are one thing to check though and they can really kill gas mileage. Another thing is how you drive - a lot of people don't realize that slow easy starts use much less gas than does fast acceleration. Keeping steady speed (not riding someone's butt) is another thing that helps mileage. Another thing is wind resistance - slow down - pushing a brick through the air at 60 mph is a lot easier than at 75.
My advice ...... be happy it runs good. Don't buy a Blazer if mpg is your expectation. They are not known for it.
#23
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Thanks for the advice. I was thinking about getting one of those, but my mechanic does not charge me to scan my vehicle. I still might get one at some point though.
#24
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OK, good luck and best wishes!
#26
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I have a 2005 GMC Jimmy. Today (Feb. 23, 2023) up in Winnipeg, Canada it's -20 deg C. i just filled up with gas, here is my fuel consumption: 318 km, 52.18 litres.
198.875 miles
11.49 gal
____________
17.30 mi/gal
On average i will get 17 to 19 miles/gal in the winter, and 20 or 21 miles/gal in the summer Odd time 23 mi/gal. Icy road conditions, bucking the wind or having auto 4wd will reduced this somewhat.
198.875 miles
11.49 gal
____________
17.30 mi/gal
On average i will get 17 to 19 miles/gal in the winter, and 20 or 21 miles/gal in the summer Odd time 23 mi/gal. Icy road conditions, bucking the wind or having auto 4wd will reduced this somewhat.
#27
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Winter blend is usually better since there is less ethanol in it. Ethanol is harder to get to 'light up' in cold weather (I have one 'toy car' that's turbocharged and was setup for E85 that absolutely hated cold temps) so they run less of it in winter vs summer. Ironically, several years back they cut back the ethanol requirements in 'summer blend' and a lot of people noticed better mileage ( I think my personal hyper-mile best then was 22mpg highway after a full cap/rotor/wire/plugs/air filter/PCV tuneup) but I think it's business as usual again. Absolutely get the EXACT OBDII reader (not all created equal but that one is verified to work with all the systems on Blazers) recommended to get some hard data to work with. If you think there's a chance it's fuel quality, find your local Farmers Co-Op and see who sells 100% Ethanol FREE gasoline around you. Between that and/or a couple bottles of Heet, you can eliminate the 'winter blend' or possibly a specific gas station with questionable storage tanks if you have been going to the same one.